What Does Gnathostomata Mean?
The word ‘gnathostomata’ relates to a group of vertebrates. It refers to vertebrates with jaws, lower as well as upper jaws. The word ‘gnathos’ means jaws. This group is an infraphylum and consists of classes of fish, birds, and other organisms which possess jaws. The group consisting of jawless animals is called ‘agnatha’. Both these groups are classified under the sub-phylum Vertebrata, phylum Chordata of Kingdom Animalia. This group is being reassessed as a group for classification. The jaws are considered to be evolved from the anterior gill support arches. The arches were adapted to propel water over the gills. The opening and closing of the mouth aided the effective pumping of water. Thus, the mouth grew stronger and bigger with time and this lead to the formation of real jaws. The modified dermal bones were transformed into teeth.
